subnet.im

AS19281Quad9

United StatesRegistryARINTypeContent

As of 7th October 2026, AS19281 (Quad9), a content network registered in the United States with ARIN, originates 5 IPv4 prefixes covering 1.3k addresses and 2 IPv6 prefixes. By IPv4 address space that makes it the 33,372nd-largest of the 79,511 networks we see originating IPv4, and the 7,582nd-largest of 18,429 in the United States. It is seen behind 8 upstream networks, most often AS42 (WoodyNet, Inc.) and AS5050 (Pittsburgh Supercomputing Center). 86% of its announcements have a valid RPKI ROA; 1 is RPKI-invalid. 86% of its routes reach at least 90% of full-feed peers.

At a glance

IPv4 prefixes

5

IPv6 prefixes

2

IPv4 addresses

1.3k

IPv6 /64s

131k

Upstream graph

The networks AS19281 is seen behind, one and two hops out, drawn from real AS paths.

AS19281Toward the internet core
Upstream graph for AS19281: 11 neighbouring networks observed beyond it across 2 levels. The same networks are listed in the tables below.AS19281Quad9This networkAS42WoodyNet, Inc.AS5050Pittsburgh Superc…AS7195EdgeUnoAS20326TeraSwitch Networ…AS49544i3D.net B.VAS6939Hurricane Electri…AS174Cogent Communicat…AS32590Valve CorporationAS2914NTT America, Inc.AS1299Arelion (fka. Tel…AS3356Lumen (Level 3)

Networks observed one and two hops upstream of AS19281 in real AS paths. A thicker line means more vantage points saw that adjacency, so weight tracks how well attested it is — not how much traffic it carries. Adjacency is an observation; whether it is a transit purchase or a settlement-free peering is an inference, and is labelled as one wherever we show it.

Neighbouring networks

25

adjacent networks

Upstreams
832%
Peers
1768%
Downstreams
00%

Networks carrying this one's traffic toward the rest of the internet.

Upstreams of AS19281
NetworkCountryRelationshipPathsVantage pts
AS42WoodyNet, Inc.USPeer275122
AS5050Pittsburgh Supercomputing CenterUSPeer8080
AS49544i3D.net B.VNLPeer7234
AS7195EdgeUnoCOPeer199
AS20326TeraSwitch Networks Inc.USPeer126
AS58511Swoop (Anycast Global Backbone)AUPeer84
AS198385AlpineDC SACHPeer31
AS1930Fundacao para a Ciencia e a Tecnologia, I.P.PTPeer11

Prefixes

The largest blocks AS19281 originates, widest first.

Largest prefixes originated by AS19281
PrefixAddressesVisibility
9.9.9.0/2425681/81
147.72.242.0/2425680/81
149.112.112.0/2425681/81
149.112.149.0/2425681/81
199.249.255.0/2425681/81
2001:690:200c::/4865.5k × /641/65
2620:fe::/4865.5k × /6465/65

Routing health

How AS19281's own announcements validate against RPKI and how far they propagate. The same measures for the whole routing table are on the routing table in numbers.

RPKI origin validation

  • Valid85.7%6
  • Invalid14.3%1
  • No ROA0.0%0

Propagation

  • Globally propagated90% of full-feed peers or more85.7%6
  • Partially propagated40% to 90%0.0%0
  • Seen by few peersUnder 40%14.3%1

Prefix sizes

IPv4 — 5 prefixes

IPv6 — 2 prefixes

  • /4865.5k × /64100.0%2

Recent changes

Announcements that started or stopped since 10th Sept 2026.

Routing data derived from RouteViews MRT archives, BGPKIT relationship inference and public registry data.